High pressure press and method of making the same

ABSTRACT

Various embodiments of high pressure presses and related methods of manufacturing and operating such presses are described. In one embodiment, a cubic press is described having press bases with spacers disposed between adjacent press bases. Sets of two or more tie bars are also disposed between adjacent press bases. The tie bars are placed in a state of compression while the spacers are placed in a state of compression. During operation, the press bases may become displaced relative to one another such that additional tension is experience by the tie bars while the amount of compression experienced by the spacer is reduced. The tie bars exhibit a relatively small cross-sectional area as compared to the cross-sectional area of the spacer.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit of each of U.S. ProvisionalPatent Application No. 61/256,209 filed Oct. 29, 2009, U.S. ProvisionalPatent Application No. 61/256,219 filed Oct. 29, 2009, U.S. ProvisionalPatent Application No. 61/256,248 filed Oct. 29, 2009 and U.S.Provisional Patent Application No. 61/256,267 filed Oct. 29, 2009, thedisclosures of each which are incorporated by reference herein in theirentireties.

BACKGROUND

High pressure presses have been used for decades in the manufacture ofsynthetic diamond. Such presses are capable of exerting a high pressureand high temperature on a volume of carbonaceous material to createconditions for sintering polycrystalline diamond. Known designs for highpressure presses include, but are not limited to, the belt press, thetetrahedral press, and the cubic press.

FIG. 1 shows a basic design for a conventional cubic press 10 known inthe art.

The design generally includes six press bases 12, with each press base12 facing towards a common central point 14. The press bases 12 have agenerally conical shape, with an outer surface 16 and an inner surface18. The inner surface 18 houses a piston 20, which is capable of beingdisplaced towards the central point 14.

FIG. 2 shows a close-up view of components surrounding the central point14 of the cubic press 10. Guide pins 22 help to keep the pistons 20aligned as they move in and out. Tooling 24 is coupled to each ofpistons 20 and may include a square-shaped surface 26 alignedperpendicularly to the axis of motion of the piston 20. Thesquare-shaped surfaces 26 of the tooling 24 converge upon a definedcube-shaped volume. This volume may be occupied with a cube-shapedreaction cell upon which the square shaped surfaces 26 apply pressureand heat to create the conditions necessary to form synthetic diamond.

In ideal operation, the cubic press 10 operates by applying force inequal amounts and directions to all six sides of the cubic volume.However, even relatively minor imbalances in the amount or direction offorce applied to any one side of the cubic volume can lead to the cubicpress not operating properly and may damage components of the cubicpress.

Referring back to FIG. 1, one known design of a cubic press 10 is shown.The press includes a plurality of tie bars 28 that may generallycomprise large diameter bolts having a capped end and a threaded end.For example, in one embodiment, the bolts may exhibit a diameter ofapproximately nine (9) inches. The tie bars 28 are positioned so as toextend between each pair of adjacent press bases 12. Pockets are formedthrough the press bases 12 for receiving the tie bars 28. The threadedend of a tie bar 28 is passed through a pocket in a first press base anda pocket in a second press base adjacent to the first press base suchthat the capped end abuts or is flush with a surface of the first pressbase. A nut is screwed on the threaded end of the tie bar 28 andtightened against the second press base thereby placing the tie bar 28in tension between pairs of adjacent press bases 12. The cumulativeeffect of tie bars 28 being positioned between each pair of adjacentpress bases is the formation of a tie bar frame that attempts to providestability to the cubic press 10 and help counteract any unequaldistribution of force and the associated stress this may otherwise placeon the high pressure press.

As also shown in FIG. 1, conventional cubic presses may include a spacer30 positioned between each pair of adjacent press bases 12. The spacer30 may be configured as a quarter section of a hollow tube and may beused to help position the press bases 12 in the desired cubicconfiguration. That is to say, the spacers 30 may have a lengthapproximately equal to the distance that the press bases 12 should bespaced apart from one another. While the tie bars 28 are placed in atensile stress condition, the spacers 30 are placed under compressionbetween pairs of adjacent press bases 12. It is noted that the spacers30 also have a much smaller cross sectional area as compared to thecross sectional area of the tie bars 28 (as taken in a directionsubstantially perpendicular to their respective lengths). Additionally,the spacers 30 conventionally act to position the bases with respect toeach other only when the press 10 is in a pressurized condition. Thistype of loading cycle is also detrimental to the fatigue life of thespacers and associated components.

However, due to design weaknesses in, for example, load cycling andalignment of the press bases 12, tie bars 28 and spacers 30 of theabove-described configuration, high cyclical bending stresses are ofteninduced, for example, in the threads of the tie bars 28 and thehydraulic cavities of the press bases 12 leading to a significantreduction in the fatigue life of the cubic press components.

For example, the press bases in the above-described configuration may bemore likely to fail after fewer cycles due to, for example, themachining out large diameter pockets in the press bases for receipt ofthe large diameter tie bars (i.e., the removal of a substantial amountof material from the press bases).

Further, with respect to alignment of the components of the cubic press,the above described configuration provides no means for helping toensure proper alignment of the components.

In addition to potential issues pertaining to alignment and fatigue, theabove configuration is also difficult to manufacture and assemble.

With respect to the manufacture of the above described cubic press, thecomponents of the cubic press are each difficult and costly to produce.For example, the process of machining out large quantities of materialfrom a press base to form a pocket for receiving a large diameter bolt,including achieving desired tolerances in such components, is anexpensive and difficult manufacturing task.

Furthermore, manufacture and assembly of the above-described cubic pressis often difficult and lacking in accuracy. For example, alignment andinstallation of the large diameter bolt within the pockets of theassociated bases is a difficult and time consuming task. Likewise,applying the necessary and desired torque to tighten the large nut on alarge diameter screw is a labor intensive, potentially dangerous, andinaccurate process.

Thus, it would be advantageous to provide an improved high pressurepress configuration design and method of making the same.

SUMMARY

The present disclosure relates generally to high pressure presses andmethods of making the same. In one embodiment, the disclosure relates tohigh pressure presses including a spacer and a plurality of tie barsextending between each pair of adjacent press bases of the high pressurepress.

In accordance with one embodiment, a high pressure press is providedwhich comprises two or more press bases including pistons that aredisplaceable towards a common central point. A first spacer extendsbetween a first press base and a second, adjacent press base of the twoor more press bases. A first set of two or more tie bars extends betweenthe first press base and the second press base with the tie bars beingarranged about the periphery of an associated spacer. In one particularembodiment, the spacer may be in a state of compression while each ofthe tie bars of the first set may be in a state of tension.

In accordance with another embodiment of the present invention, a methodof manufacturing a high pressure press is provided. The method includesabutting a first end of a spacer with a surface of a first press baseand abutting a second press base with a second end of the spacer. Afirst set of two or more tie bars is positioned between the first pressbase and the second press base by inserting each tie bar of the firstset through an associated tie bar pocket of the first press base and anassociated tie bar pocket of the second press base. Each tie bar of thefirst set is tensioned.

In accordance with another embodiment of the present invention, a methodof operating a high pressure press is provided. The method includesconfiguring a plurality of press bases such that a piston of each pressbase may be displaced towards a common region. At least one spacerbetween a first press base and a second press base of the plurality ofpress bases and the at least one spacer is placed in a state ofcompression when the high pressure press is in a state of rest. Aplurality of tie bars is coupled to each of the first press base and thesecond press base and the plurality of tie bars is placed in a firststate of tension while the high pressure press is in a state of rest.Each piston is displaced towards a common region and applies force to anobject at or near the common region. The tie bars are placed in a secondstate of tension, greater than the first state of tension, while thepistons are applying force to the object.

Features from any of the above mentioned embodiments may be used incombination with one another, without limitation. In addition, otherfeatures and advantages of the instant disclosure will become apparentto those of ordinary skill in the art through consideration of theensuing description, the accompanying drawings, and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a perspective view of a conventional cubic press known inthe art.

FIG. 2 shows a perspective view of a center point of the press shown inFIG. 1.

FIG. 3 shows a perspective view of a high pressure press according to anembodiment of the instant disclosure.

FIG. 4 shows a perspective view of a press base of the high pressurepress illustrated in FIG. 3 having spacers secured thereto.

FIG. 5 shows a perspective view of a press base of the high pressurepress illustrated in FIG. 3.

FIG. 6 shows a perspective view of a press base of the high pressurepress illustrated in FIG. 3.

FIG. 7 shows a close-up perspective view of an outside side surface of apress base according to an embodiment of the instant disclosure.

FIG. 8 shows a perspective view of a spacer according to an embodimentof the instant disclosure.

FIG. 9 is a graph showing the effect of the A_(S)/A_(T) ratio on thestress carried by tie bars and the spacer during a press cycle of a highpressure press according to an embodiment of the instant disclosure.

FIG. 10 shows a perspective view of a partially constructed highpressure press during a preliminary step of manufacturing a highpressure press according to an embodiment of the instant disclosure.

FIG. 11 shows a perspective view of a partially constructed highpressure press during an intermediate step of manufacturing a highpressure press according to an embodiment of the instant disclosure.

FIG. 12 shows a perspective view of a press base that may be added to apartially constructed high pressure press during a step of manufacturinga high pressure press according an embodiment of the instant disclosure.

FIG. 13 shows a perspective view of a partially constructed highpressure press during an intermediate step of manufacturing a highpressure press according to an embodiment of the instant disclosure.

FIG. 14 shows a perspective view of a partially constructed highpressure press during an intermediate step of manufacturing a highpressure press according to an embodiment of the instant disclosure.

FIG. 15 shows a perspective view of a high pressure press according toanother embodiment of the instant disclosure.

Throughout the drawings, identical reference characters and descriptionsindicate similar, but not necessarily identical, elements. While theembodiments described herein are susceptible to various modificationsand alternative forms, specific embodiments have been shown by way ofexample in the drawings and will be described in detail herein. However,the embodiments described herein are not intended to be limited to theparticular forms disclosed. Rather, the instant disclosure covers allmodifications, equivalents, and alternatives falling within the scope ofthe appended claims.

DETAILED DESCRIPTION

The instant disclosure relates generally to high pressure presses andmethods of making high pressure presses. In one embodiment, a highpressure press may include a spacer and plurality of tie bars positionedbetween each pair of adjacent press bases of the high pressure press. Inone embodiment, the plurality of tie bars may surround the periphery ofthe spacer. Furthermore, each tie bar may be in tension while the spacermay be in compression. Such a configuration provides a high pressurepress having improved alignment of the bases, while also making the highpressure press easier to manufacture, assemble and repair.

For purposes of explaining the features of the high pressure pressesdisclosed herein, a cubic high pressure press will be described andillustrated. However, the high pressure presses disclosed herein are notlimited to a cubic configuration. For example, the features of the highpressure presses disclosed herein may also be used in a tetrahedralpress.

As shown in FIG. 3, a high pressure press 100 comprises six press bases110 configured in a cubic orientation. By cubic orientation it is meantthat each press base 110 is positioned so that its central axis pointsat, and is perpendicular to, a different face of a cubic reaction celllocated about a central region 102 of high pressure press 100 duringoperation. High pressure press 100 also comprises six pistons 120, whichmay each be housed in a piston cavity 114 of an associated press base110. While not labeled or viewable in FIG. 3, piston cavity 114 is shownin FIGS. 4, 5 and 6. Pistons 120 may move in and out of press base 110towards and away from central region 102 of high pressure press 100.Outward movement of piston 120 towards the central region 102 may beaccomplished by any suitable mechanism for moving a piston. In oneexample, the introduction of hydraulic fluid into the bottom (or someother portion) of piston cavity 114 in press base 110 forces piston 120to move out of piston cavity 114 and towards central region 102. Toolingmay be included at the end of piston 120 closest to central region 102.The tooling may include, for example, a flat, square surface that isperpendicular to the axis of motion of piston 120 and which will pressagainst a side of the cubic reaction cell located at central region 102during operation of high pressure press 100.

When pistons 120 begin to move in towards central region 102 and applypressure against the cubic reaction cell, it is desirable that highpressure press 100 apply pressure to all sides in equal or substantiallyequal amounts in order to, among other things, avoid or limit theintroduction of stress in various components of high pressure press 100.Where pressure is not applied equally on all sides (or where pressure isequally applied, but asymmetric loading or stress is still experiencedby the tie rods or bases), the negative effects of such an imbalance(which may include, for example, crack formation and propagation incomponents of the of press 100) may be mitigated or eliminated by addingsupport structures between press bases 110 as described in greaterdetail hereinbelow. The endurance limit, or the ability to handle theapplication of cyclic stress states without mechanical or materialfailure, of various components of the high pressure press 100 (e.g., thepress bases 110) may be improved substantially by the implementation ofthe support structure described herein.

In the embodiment described with respect to FIG. 3, a support structuremay include a spacer 140 extending between each pair of adjacent pressbases 110 and a set of two or more tie bars 150 extending between eachpair of adjacent press bases 110. In one embodiment, the spacer mayinclude a structure that exhibits a relatively large diameter orcross-sectional area as compared to the diameter or cross-sectional areaof an individual tie bar. For example, in one embodiment, a spacer 140may exhibit a diameter of approximately 9 inches and the tie bars mayexhibit a diameter of approximately 1.75 inches, although other sizesand size ratios are also contemplated. As shown in FIG. 3, tie bars 150may be arranged about the periphery of spacer 140 (i.e., about theperiphery of the spacer's cross-section as taken substantiallyperpendicular to a longitudinal axis of the spacer extending betweenassociated, adjacent press bases 110). Tie bars 150 may be arrangedabout the periphery of spacer 140 such that tie bars 150 are evenlyspaced about the periphery of spacer 140, although other uneven orgeometrically asymmetrical spacing arrangements may also be used. In oneembodiment tie bars 150 may be positioned such that they abut or arecontiguous with the spacer 140. In another embodiment, tie bars 150 maybe set off from or spaced relative to the spacer 140 so that a gapexists between the sides of tie bars 150 and the side of spacer 140.Also, as shown in FIG. 3, tie bars 150 may be aligned to besubstantially parallel with spacer 140 as they extend between adjacentpress bases 110.

Spacers 140 and tie bars 150 may have any suitable shape for providingstability to high pressure press 100. As shown in FIG. 3, spacer 140 andtie bars 150 may exhibit substantially cylindrical shapes. In oneembodiment, all of the tie bars 150 of a given high pressure press 100may exhibit the same or similar geometry. Similarly, in one embodiment,all of the spacers 140 of a high pressure press 100 may exhibit the sameor similar geometries, whether or not they be generally similar in shapeor geometry to tie bars 140. In another embodiment, different spacers140 of the same high pressure press 100 may exhibit different shapes,just as different tie bars 150 of the same high pressure press 100 mayhave different shapes. Furthermore, as indicated above, spacers 140 andtie bars 150 of the same high pressure press 150 may have the same shapeor different shapes.

Referring now to FIGS. 4, 5 and 6, the manner of positioning tie bars150 and spacer 140 between adjacent press bases 110 is described andillustrated.

With respect to spacer 140, the ends 142 of spacer 140 may be positionedto abut an outer side surface 112 of two adjacent press bases 110.Spacers 140 may be placed under compression as will be described infurther detail below. The use of a spacer 140 placed in compression andhaving a relatively large cross-sectional area may provide a morereliable joint between associated press bases 110 than previously useddesigns that rely heavily on tensioned elements. Positioning spacers 140by abutting them against outer side surface 112 of press bases 110provides an advantage over previously known configurations.Particularly, the press bases 110 may be easier and less costly tomanufacture.

Referring now to FIGS. 5 and 7, press base 110 may include a recessed orshouldered surface, referred to herein generally as an indent 116 (orindentation), on outer side surface 112 for receiving and aligningspacer 140. Indent 116 may have a shape approximate the cross-sectionalshape of spacer 110 such that indent 116 receives and aligns spacer 140when spacer 140 is positioned against press base 100. In one embodiment,as shown in FIG. 7, indent 116 may include rounded corners 117 togenerally conform to the circular cross-section of spacer 140. Ofcourse, as noted previously, the spacer may exhibit othercross-sectional geometries and, therefore, the indent may be configuredto accommodate such.

As also shown in FIG. 7, indent 116 may also include a straight wallportion 118 between rounded corners 117. Straight wall portion 118 maybe used in conjunction with a notch 144 located at ends 142 of spacer140, as shown in FIG. 8, to prevent spacer 140 from rotating withinindent 116. For example, if indent 116 and spacer 140 are both circular(or if indent 116 is “oversized” compared to the cross-sectionalgeometry of the spacer 140), spacer 140 may freely rotate within indent116. However, by implementing straight wall portion 118 and notch 144with the spacer 140 being positioned such that the notch 144 engages thestraight wall portion 118, spacer 140 will not be able to freely rotatein indent 116.

The above features of the disclosed embodiment may assist in assuringthat high pressure press 100 is properly aligned. Indent 116 may beformed on outer side surface 112 of press base 110 with a desired levelof accuracy and precision, thereby ensuring proper alignment of spacers140. As mentioned briefly above, misalignment of press bases 110 of highpressure press 100 may be a factor in failure of components of highpressure presses and, therefore, the above features help to reduce thepossibility of misalignment.

FIGS. 4, 7 and 8 also illustrate the securement of spacer 140 to sidesurface 112 of press base 110. FIG. 7 shows that an aperture or a firstspacer securing pocket 119 may be formed through a portion of indent116. First spacer securing pocket 119 may or may not pass all the waythrough press base 110. FIG. 8 shows that spacer 140 may likewiseinclude an aperture or a second spacer securing pocket 146. First andsecond spacer securing pockets 119, 146 may be used in conjunction tosecure spacer 140 to press base 110. For example, spacer 140 may bealigned in indent 116 such that first and second spacer securing pocket119, 146 are aligned with one another. Then, where first spacer securingpocket 119 extends through press base 110, a bolt or some otheralignment or securing mechanism may be inserted into first spacersecuring pocket 119 from the opening opposite the opening in indent 116.The bolt or other aligning or securing mechanism may then pass throughthe opening in indent 116 and into second spacer securing pocket 146 ofspacer 140. In one embodiment, second spacer securing pocket 146 may,e.g., include female threads to receive male threads of the bolt orother alignment or securing means to thereby allow spacer 140 to becoupled with press base 110. FIG. 4 illustrates the result of securingspacers 140 to press base 110 in accordance with one embodiment.

Unlike spacers 140 that may abut outer side surfaces 112 of press bases110, the plurality of tie bars 150 positioned between adjacent pressbases 110 extend into and through a portion of the press bases 110 andare then put under tension. As shown in FIGS. 5-7, tie bars 150 mayextend through press bases 110 via holes or apertures in press bases110, referred to as tie bar pockets 152 herein. Tie bar pockets 152 mayextend through press bases 110 from outer side surface 112 of pressbases 110 to a tie bar cavity 111 in press base 110 as illustrated inFIG. 6. Tie bar cavity 111 may be formed in a surface of press base 110that is generally opposite the surface of press base 110 having pistoncavity (not shown) formed therein. Tie bar cavity 111 in press base 110may serve to provide a surface generally perpendicular to the axis oftie bars 150 as they pass through press bases 110. In this manner, asecuring means, such as a nut or other fastener, may be tightenedagainst the surface of the tie bar cavity 111 so as to tension tie bars150 after they are in place between adjacent press bases. As shown inFIG. 6, tie bar cavity 111 may provide four such surfaces to accommodatetie bars 150 passing through press base 110 from four differentdirections (i.e., the surfaces lie in planes that are not parallel toone another). Tie bar cavity 111 of press base 110 may include more orfewer surfaces depending on the configuration of high pressure press100.

The openings of tie bar pockets 152 at outer side surface 112 may bearranged about indent 116 such that when tie bars 150 and spacer 140 arepositioned between adjacent press bases 110, tie bars 150 are arrangedabout the periphery of spacer 140 as discussed above. In one embodiment,and as noted previously, tie bar pockets 152 may have a shapeapproximately equal to the cross sectional shape of tie bars 150 inorder to provide a close fit for tie bars 150. For example, where tiebars 150 are cylindrical, tie bar pockets 152 may have a circular shapewith a diameter approximately equal to the outer diameter of tie bars150, but large enough to accommodate passage of the tie bars 150therethrough.

Tie bars and corresponding tie bar pockets 152 are relatively small incross-sectional area as compared to associated spacers 140, and theirinstallation through press bases 110 do not require that large amountsof material be removed from press bases 110. Accordingly, the overallstrength of each press base 110 is generally maintained after tie barpockets 152 are formed. A plurality of smaller tie bar pockets 152 isalso easier and less expensive to manufacture in press base 110 than thelarge diameter spacer pockets used in previously known designs.Moreover, smaller tie bar pockets 152 may be formed with greaterprecision and accuracy (as compared to prior art designs), therebyimproving the overall alignment of high pressure press 100.

Tie bars 150 may be any suitable structure for passing through adjacentpress bases 110 and being placed under tension. In the embodimentsillustrated, tie bars 150 may include bolts having a capped end, the capbeing larger than openings of tie bar pockets 152, and a threaded end.The threaded end of tie bar 150 may be first inserted into an opening ofa tie bar pocket 152 in tie bar cavity 111 of press base 110 and passedthrough press base 110 until the threaded end emanates from outer sidesurface 112 of press base 110. The threaded end may then be insertedinto a corresponding opening of tie bar pocket 152 in outer side surface112 of a press base 110 located adjacent the first press base 110 thattie bar 150 was passed through. The threaded end then emanates from tiebar pocket 152 in tie bar cavity 111 of the adjacent press base 110. Atthis point, the capped end of tie bar 150 may be flush against orotherwise abut the opening of tie bar pocket 152 in tie bar cavity 111of the first press base 110 (of course, it is noted that washers orother similar components might be installed between the cap and thepress base). A nut, or other appropriate fastening device may then becoupled with the threaded end of tie bar 150 and tightened so as toplace the tie bar 150 in tension (again, it is noted that washers orother components might be installed between the nut and press base). Inanother embodiment, both ends if the tie bar 150 may be threaded andnuts or other threaded members may be coupled to each end of the tie bar150.

By using relatively small cross-sectional area (e.g., small diameter)tie bars 150, the amount of tension experienced by each tie bar 150 maybe closely and accurately controlled. For example, considering theabove-described embodiment, the amount of torque applied to each nut ofa given tie bar 150 is significantly more controllable than when largernuts and tie bars are being used, and therefore the amount of tensionapplied to each tie bar 150 may be accurately controlled. However, thetie bars may also be placed in tension by other means. For example, inone embodiment, tie bars 150 may be hydraulically tensioned within +/−1%of a desired level of tension, as compared to previous designs whichonly allowed accuracy to within +/−10%. More accurate tensioning of tiebars 150 may lead to more overall stability of high pressure press 100and less fatigue of such components.

The plurality of tensioned tie bars 150 act in conjunction with oneanother to distribute stress substantially equally amongst the pluralityof tie bars 150 about the periphery of the space 140. In distributingstress in a generally uniform manner, any number of tie bars 150 greaterthan one may be used between each pair of adjacent press bases 110. Agreater number of tie bars 150 allows for a greater distribution ofstress, and correspondingly, either less stress per tie bar 150 or useof tie bars with smaller cross-sectional areas. However, spaceconstraints may limit the number of tie bars 110 that can be usedbetween a pair of adjacent press bases 110. In one example, eleven tiebars 150 may be positioned between each pair of adjacent press bases110. Tie bars 150 may be spaced evenly around the periphery of spacer140 or may be spaced apart from each other at uneven distances.

Referring back to FIG. 3, spacer 140 is illustrated as having a largercross-sectional area than the cross-sectional area of each tie bar 150.A spacer 140 with a large cross-sectional area allows thecross-sectional area of tie bars 150 to be smaller without drasticallyinfluencing the reliability of the joint. Furthermore, tie bars 150having a large length to diameter ratio are less sensitive to bendingstresses in general, and therefore add to the overall stability of thejoints.

The ratio of the cross-sectional area of spacer 140 (A_(S)) to the sumof the cross-sectional areas of tie bars 150 (A_(T)), the ratio beinghereinafter referred to as A_(S)/A_(T), has been found to be a valuethat impacts the effect of a press cycle on the joint between adjacentspacers, and correspondingly, the fatigue life of the components of highpressure press 100. In general terms, a higher A_(S)/A_(T) value resultsin less force being applied to tie bars 150 over the course of a presscycle, and therefore likely prolongs the life of components of highpressure press 100 due to the application of less stress per cycle. FIG.9 illustrates this concept. Multiple high pressure presses according tothe disclosed embodiment, having varying A_(S)/A_(T) ratios, weresubjected to the same press cycle. The graph illustrates the load (orforce) experienced by tie bars 150 during a press cycle and as well asthe load (or force) experienced by a spacer 140 during a press cycle.The “Force” axis is normalized such that represents a magnitude of forceapplied to the specified components. When the A_(S)/A_(T) ratio(indicated in FIG. 9 as R) was 0.5, the force applied to tie bars 150(being pre-loaded in a tensile state) jumped from 100% (i.e., preloadcondition) to about 150% of preload condition during the press cycle,while the force applied to spacer 140 (being pre-loaded in a compressivestate) dropped from 100% of preload condition to about 75% of preloadcondition. When the A_(S)/A_(T) was increased to 10, the force appliedto tie bars 150 changed only a relatively tiny amount during the presscycle, while the force applied to spacer 140 took a significant drop toless than 50% of preload condition. The only minor increase in forceapplied to tie bars 150 during the press cycle when the A_(S)/A_(T)ratio was 10 will likely result in a longer overall life for the highpressure press, since tie bars 150 are not undergoing large amounts ofstress every cycle that will tend to cause failure in high pressurepress components.

Accordingly, high pressure press 100 may preferably have a A_(S)/A_(T)greater than 0.5, more preferably a A_(S)/A_(T) greater than 5.0, andmost preferably a A_(S)/A_(T) ratio greater than 10.

It is noted that the above-described embodiment may also becharacterized as having a plurality of springs positioned between thepress bases 110 and that the above ratio A_(S)/A_(T) is derived from astiffness ratio of the tie bars and spacer. Thus, the stiffness ratio,while described as being altered through manipulation of cross-sectionalareas in the example above, may be also be manipulated in other ways,such as by altering the materials from which the components are made.Thus, tie bars 140 may be considered as a plurality of springs intension with each exhibiting a relatively low spring constant (k). Thespacer 140 may be considered as a spring in compression with arelatively large spring constant.

In one embodiment, when the press 100 is assembled, such as shown inFIG. 1, tie bars 150 may be placed in tension up to, for example, 95% oftheir elastic limit. On the other hand, the spacer 140 may be placed incompression at a level of, for example, less than approximately 5% ofits elastic limit. During operation of the press 100 (i.e., when pistons120 are actuated and applying pressure to a cubic reaction cell) pressbases 110 may become slightly displaced relative to one another. Underconventional operating conditions, tie bars 150 will experienceadditional tension (although not typically exceeding their yieldstrength) while spacer 140 may see a reduction in the magnitude ofcompression, although it may not necessarily experience a zero load (orcomplete lack of compression loading). Such a configuration enhances thefatigue life of the press 100 including components such as press bases110, spacers 140 and tie bars 150.

In addition to improved fatigue life, the above described embodimentprovides a variety of other advantages. For example, repair work iseasily facilitated with such a configuration. If a component were tofail, for example, due to overloading or fatigue, the above describedembodiment is configured such that the most likely component to showfailure would be the tie bars 150. Tie bars 150 are easily replaced asis apparent from the discussions above. Additionally, tie bars 150 areone of the less expensive and less difficult components of the press 100to manufacture. Moreover, the above-described embodiment retains arelatively “open” configuration to provide ready access to the cubicreaction cell during intended operation of the press 100 as well as toprovide access to the pistons 120 and related components for bothroutine and unexpected maintenance or repair.

In another embodiment of the instant disclosure, a method ofmanufacturing a high pressure press may include positioning a first endof one or more spacers at a first press base, positioning a second pressbase at a second end of at least one of the spacers, coupling two ormore tie bars with each of the first press base and the second pressbase, and tensioning the two or more tie bars extending between thefirst press base and the second press base. Additionally, the method mayinclude placing the spacer in a compressive stress state.

FIG. 10 illustrates a first act of the method. Press base 210 a isillustrated as having first ends of one or more spacers 240 a positionedat desired locations relative to the press base. In the embodiment shownin FIG. 10, four spacers 210 a are positioned on press base 210 a.However, the number of spacers 240 a positioned on or about the pressbase 210 a is not so limited. FIG. 10 also shows spacers 240 a equallyspaced about press base 210 a, although spacers 240 a need not beequally spaced.

As described previously, spacers 240 may be positioned relative to pressbase 210 a by having a first end of spacer 240 a abut outside sidesurface 212 of press base 210 a. Alignment of spacer 240 a on press base210 a may be guided by an indentation, recess or shouldered surface inoutside side surface 212 of press base 210 a as described in greaterdetail previously. Furthermore, to hold spacer 240 a in position onoutside side surface 212 of press base 210 a, spacer 240 a and pressbase 210 a may include spacer securing pockets. A spacer securing pocketin spacer 240 a may be aligned with a spacer securing pocket in pressbase 210 a, followed by inserting an alignment structure or a securingstructure or mechanism into both spacer securing pockets as described ingreater detail above.

Following positioning of spacers 240 a on press base 210 a, additionalpress bases 210 b may be positioned relative to a second end of at leastone of spacers 240 a. As shown in FIG. 11, additional press bases 210 bare positioned on two of spacers 240 a. As with press base 210 a, pressbases 210 b may be aligned with spacers 240 a via indentations, recessesor shouldered surfaces located on outside side surfaces of press bases210 b. Additionally, press bases 210 b may be secured to spacers 240 aby aligning spacer securing pockets in each component and extending asecuring structure or mechanism, such as a bolt, into both press bases210 b and spacers 240 a.

Press bases 210 b as shown in FIG. 11 only have spacers 240 a positionedrelative thereto. However, as shown in FIG. 12, press bases 210 c mayhave spacers 240 c positioned thereon prior to being positioned onspacers 240 a. For example, after positioning press bases 210 b relativeto spacers 240 a, press bases 210 c as shown in FIG. 12 may then bepositioned relative to press bases 210 b and 210 a. The result isillustrated in FIG. 13, wherein spacers 240 c are positioned betweenpress bases 210 b and 210 c to form a ring-like structure. Positioningof spacers 240 c between press bases 210 b and 210 c may be accomplishedas described above, such as by using indentations in press bases 210 band 210 c for alignment and spacer securing pockets and securing meansto secure spacers 240 c to press bases 210 b and 210 c. It should alsobe noted that spacers 240 a and 240 c shown in FIG. 13 will be placedunder compression as with other spacers described herein.

In order to complete the basic frame of the high pressure press, a pressbase 210 d, which is identical to press base 210 a illustrated in FIG.10, may be positioned at the top of the high pressure press (referringto the orientation shown in FIGS. 10-14) as shown in FIG. 14. Press base210 d includes one or more spacers 240 d which have been positionedrelative to press base 210 d, and possibly coupled thereto, prior topositioning press base 210 d on the partially completed high pressurepress frame. Spacers 240 d may be positioned relative to press base 210d by using indentations on press base 210 d and by using spacer securingpockets and securing mechanisms as described above.

Upon completion of the basic frame of the high pressure press as shownin FIG. 14, tie bars may be positioned between adjacent press bases asdescribed in greater detail above. For example, press bases 210 a, 210b, 210 c, and 210 d may each include tie bar cavities and tie barpockets to enable tie bars to be coupled with adjacent press bases andplaced under tension. Tensioning of tie bars may be accomplished by anysuitable means. In one example, the tie bars are bolts having a cappedend and a threaded end, and are tensioned by twisting a nut on to thethreaded end of the tie bars to a specified level of torque. In anotherembodiment, the tie bars may include bolts that are placed in tensionwith a hydraulic pulling assembly and subsequently released afterinstallation of a nut or other fastening component.

The method may include an additional act of tensioning the tie barsaccording to a predetermined order. For example, one tie bar (or anotherspecified number of tie bars) between each adjacent pair of press basesmay be tensioned before a additional tie bars between any adjacent pairof press bases may be tensioned. Alternatively, all of the tie barsbetween one adjacent pair of press bases may be tensioned before anyother tie bars are tensioned. Additionally, the order of tensioning thetie bars about the periphery of a spacer may be prescribed. For example,the tie bars may be tensioned in a “star pattern” or some in some otherpredetermined pattern or order.

Referring briefly to FIG. 15, a press 100′ is shown in accordance withanother embodiment of the present invention. The press 100′ is similarto that which has been describe above with respect, for example, to FIG.3 and may include six press bases 110 configured in a cubic orientationwith each press base 110 is positioned so that its central axis pointsat, and is perpendicular to, a different face of a cubic reaction celllocated about a central region 102 of high pressure press 100 duringoperation. Press 100 also comprises six pistons 120, which may each behoused in a piston cavity 114 of an associated press base 110 andconfigured such has been described hereinabove.

In the embodiment described with respect to FIG. 15, a support structuremay include a spacer 140′ extending between each pair of adjacent pressbases 110 and a set of two or more tie bars 150 extending between eachpair of adjacent press bases 110. Spacer 140′ may be configured as agenerally tubular member, or as a body with a cavity extendingtherethrough. Tie bars 150 may be arranged about the internal peripheryof spacer 140 (i.e., within the cavity) such that tie bars 150 areevenly spaced thereabout, although other uneven or geometricallyasymmetrical spacing arrangements may also be used. In one embodimenttie bars 150 may be positioned such that they abut or are contiguouswith the spacer 140′. In another embodiment, tie bars 150 may be set offfrom or spaced relative to the spacer 140′ so that a gap exists betweenthe sides of tie bars 150 and the internal periphery of spacer 140′.Also, tie bars 150 may be aligned to be substantially parallel with aninternal surface of the spacer 140 as they extend between adjacent pressbases 110.

It is noted that other components may be used in place of those shownand described regarding, for example, the spacers and tie bars. Forexample, tie bars may include any of a variety of tensile elementsincluding, for example, cables or other structures relatively strong intension.

While certain embodiments and details have been included herein forpurposes of illustrating aspects of the instant disclosure, it will beapparent to those skilled in the art that various changes in systems,apparatus, and methods disclosed herein may be made without departingfrom the scope of the instant disclosure, which is defined, in part, inthe appended claims. The words “including” and “having,” as used hereinincluding the claims, shall have the same meaning as the word“comprising.”

What is claimed is:
 1. A high pressure press comprising: six press bases positioned to provide a cubic press configuration, each press base including a piston displaceable towards a common central region; a plurality of spacers, each spacer extending between at least one press base of the six press bases and an adjacent press base of the six press bases; and a plurality of sets of tie bars, each set of tie bars including two or more tie bars extending between at least one press base of the six press bases and an adjacent press base of the six press bases, each set of tie bars being arranged adjacent a periphery of an associated spacer.
 2. The high pressure press of claim 1, wherein the at least one spacer of the plurality of spacers is under compression and wherein each tie bar associated with the at least one spacer is under tension.
 3. A high pressure press comprising: two or more press bases including pistons displaceable towards a common central region; a first spacer extending between a first press base and a second, adjacent press base of the two or more press bases, wherein the first spacer is bolted to at least one of the first press base and the second press base; and a first set of two or more tie bars extending between the first press base and the second press base and arranged adjacent a periphery of an associated spacer.
 4. The high pressure press of claim 1, wherein each tie bar extends substantially parallel to its associated spacer.
 5. The high pressure press of claim 1, wherein each spacer exhibits a substantially cylindrical shape.
 6. The high pressure press of claim 5, wherein each set of two or more tie bars is arranged about a circumference of its associated spacer.
 7. The high pressure press of claim 5, wherein each tie bar exhibits a substantially cylindrical shape.
 8. A high pressure comprising: two or more press bases including pistons displaceable towards a common central region; a first spacer extending between a first press base and a second, adjacent press base of the two or more press bases; and a first set of two or more tie bars extending between the first press base and the second press base and arranged adjacent a periphery of an associated spacer; wherein the first spacer has a cross-sectional area A_(S), the first set of two or more tie bars has a combined cross-sectional area A_(T), and the value of A_(S)/A_(T) is greater than 0.5.
 9. The high pressure press of claim 8, wherein the value of A_(S)/A_(T) is greater than 5.0.
 10. A high pressure press comprising: two or more press bases including pistons displaceable towards a common central region; a first spacer extending between a first press base and a second, adjacent press base of the two or more press bases, wherein a first end of the first spacer abuts an outer surface of the first press base and wherein a second end of the first spacer abuts an outer surface of the second press base; and a first set of two or more tie bars extending between the first press base and the second press base and arranged adjacent a periphery of an associated spacer.
 11. The high pressure press of claim 10, wherein the outer surface of the first press base includes an indentation substantially conforming to the cross-sectional shape of the first spacer, wherein the outer surface of the second press base includes an indentation substantially conforming to the cross-sectional shape of the first spacer and wherein the first end of the first spacer is positioned generally within the indentation of the first press base and wherein the second end of the first spacer is positioned generally within the indentation of the second press base.
 12. The high pressure press of claim 11, wherein the first end and the second end of the first spacer each include a notch configured to accommodate a wall of an associated indentation.
 13. A high pressure press comprising: two or more press bases including pistons displaceable towards a common central region; a first spacer extending between a first press base and a second, adjacent press base of the two or more press bases; and a first set of two or more tie bars extending between the first press base and the second press base and arranged adjacent a periphery of an associated spacer; wherein the first press base and the second press base each include tie bar receiving pockets that extend from an outer surface of its associated press base to another surface of its associated press base. 